DE1188348B - Electric motor-driven lawn mower - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

AOId

German class: 45 c -35/26

1188 348
Q567III / 45C
December 19, 1958
March 4, 1965

The previously common electric motor-driven lawnmowers have a cast aluminum or a sheet metal housing on which the impellers and the motor with the cutting blades is attached. The known lawnmowers are relatively heavy and require a considerable amount to be produced Cost of work steps, connecting and fastening elements and assembly time.

The invention is now based on the technical problem for an electric motor driven Lawn mower to create a frame in lightweight construction that with the other components in a Minimum of labor and time can be put together to form a complete lawnmower. This task is achieved according to the invention in an electric motor-driven lawnmower in that The frame is made of plastic in one piece to support the motor and the impellers as well as the handlebar and on the one hand in a hood that encapsulates the engine, on the other hand merges into a housing that covers the cutting blades.

When using the frame according to the invention, the assembly of the entire device can be can be carried out in relatively few steps. The weight is far below what you were used to before Height, which is due on the one hand to the fact that the frame, which is here at the same time the device housing forms, consists of plastic, and on the other hand is based on the fact that an input 3c baumotor can be used, eliminating the need for the metal housing otherwise required for the motor comes.

So that the motor can be easily attached to the frame, the rotor is overhung mounted on a bearing plate that can be connected to the housing, the bearing point being the cutting blades is facing. A further simplification results from the fact that the rotor bearing shield on the stator holding and centering one end face.

Around accessories, such as capacitors and similar elements, without additional covers and attachments to the lawnmower, it is advisable to place them in the hood and in the End shield to provide an extension through which a space is created in which these accessories can be accommodated.

In a preferred embodiment, the housing is curved from the hood to the Outsides. Due to this design, the frame also holds a relatively high mechanical level Stresses without further ado. For lawn mowers powered by an electric motor

Applicant:

Quick-Elektromotoren-Werk G. mb H.,
Darmstadt, Graefenhäuser Str. 85

Named as inventor:
Ernst Becker, Darmstadt;
Karl Notz, Kuhnbach

In the preferred embodiment, the housing is open on the inlet and outlet side and takes on the openings Pendulum grille on. Because of the inlet and outlet openings, the resistance of the frame in the transverse direction is reduced, transverse reinforcements are provided at these openings, which are formed by waves which at the same time accommodate the pendulum grille formed from sheet metal strips.

A good cooling of the engine and thus the possibility of reducing the weight of the engine and thus also to maintain the weight of the entire device, are preferably slot-shaped in the hood Air inlets provided.

It is advisable to use molded, superimposed recesses in the housing to accommodate the wheel bearing journals for the Provide impellers at different heights.

Further advantages and features of the invention are given in the following description of the drawing which illustrates an embodiment. It shows

F i g. 1 the lawn mower in side view, partially cut,

F i g. 2 the lawnmower in plan view,

F i g. 3 the lawnmower in front view.

The housing 1 of the lawnmower merges into a hood 2. It is made of plastic and is in Ways of pressing created. The hood 2 is designed so that it is the housing of the electric drive motor forms. Its rotor 3 is overhung in the end shield 4 via the roller bearings 5 and 6. The bearing plate 4 is also designed so that it holds the stator 7 on one end face and centering. This training allows the engine in its entirety before installation the end shield 4 are mounted so that after it has been fastened via the screws 8 on the housing 1 is installed ready for operation.

509 51700

An extension 9 is provided both on the hood 2 and in the bearing plate 4, which is intended to accommodate of electrical accessories, such as starting and / or operating capacitors 10 and circuit breakers 11, serves. As can be seen from FIG. 1, the capacitors are fastened at 12 on the end shield 4. Of the On / off switch 11, which is used to switch the motor on and off, is on the front side of the hood 2 in this way attached that its actuator, here the rocker arm 13, is on the top of the hood.

A rubber ring 14 is inserted between the hood 2 and the bearing plate 4 to prevent any vibrations absorbs dampening. The end shield consists either of insulating material or of metal and is then provided with an insulating coating.

The shaft 15 of the motor can be used at both ends for power transmission. For this it can be connected to the parts to be driven via coupling hubs. In Fig. 1 is on the cutting knives 16 facing away from such a coupling hub to see; it is denoted by 17. the Knives 16 are also fastened in a coupling hub. This forms a driver hub for the knives and is shown in FIG. 1 denoted by 18. The knives 16 are also in the driver hub 18 over a snap ring 19 acting as a quick release fastener is attached. On the side facing the engine the driver hub 18 at the same time forms a fan 20. Air inlet slots 21 are provided in the hood 2, via which the cooling air can enter the engine, from where it, through the suction of the Fan 20, flows over the motor winding and finally in the radial direction in the area of the Fan emerges from the engine compartment. The cooling air flowing out radially prevents the build-up of cut grass on the driver hub 18.

In the housing 1 vertically extending slots 22 are provided, which are widened laterally at 23, 24 and 25 so that a square can be used in a rotationally secure manner. At these points 23, 24 and 25, the bearing journals 26 of the running wheels 27 can be used. The width of the slots is chosen so that it corresponds to the diameter of the bearing pin. As a result, it is sufficient to change the height of the wheels 27 to loosen the bearing pin 26 so much that the square 28 slides on the bearing pin 26 by its thickness in the direction of arrow A out of the slot 22 or the extensions at 23 to 25 to the Move the pin to the desired height and fasten it again with its square 28 at the selected point. In order to be able to carry out changes in the height of the running wheels 27 quickly and easily, a tommy nut 29 is assigned to each bearing pin 26.

As soon as the nut 29 is loosened, the spring ring 30 presses the pin 26 in the direction of arrow A, so that the square 28 emerges from its extension and the pin 26 can be displaced as a whole. To fix it in the new position, it is now sufficient to screw the nut 29 back on.

On the top of the hood 2 eyes 31 and 32 are attached with recesses in which the On the hood side, link 33 with its ends 34 that merges into a bracket and consists of two tubes and 34 'can insert resiliently. The handlebars can be opened at any time by simply spreading the ends of the stirrups connected to or detached from the lawnmower.

The housing 1 is open on the inlet and outlet sides. A pendulum grille is attached to each of the openings. This preferably consists of stamped, edgewise sheet metal strips 35, which over spacer rollers 36 are attached to the shaft 37. Instead of the spacer rollers, in the knife housing injected spacers can be provided, which hold the sheet metal strips 35 at their distance. the The purpose of pendulum grids is to prevent unintentional access to the knife room and that Allow grass to enter the knife area unhindered on the inlet side, but prevent it when cutting, that the cut grass is thrown out of the lawnmower. They therefore cause the grass deposit in the cutting path of the mower.

In a departure from the exemplary embodiment shown, the housing can be arched from the hood to the outside so that it resembles a bridge arch in cross-section. Through this the resistance of the housing to bending is significantly increased.

Claims (5)

Patent claims: 1. Electrically powered lawn mower, characterized in that the frame of which is made in a single piece of plastic, as a support for the motor, the wheels and the handlebars and on the one hand in a motor encapsulating receiving Hood, on the other hand, merges into a housing that covers the cutting blades. 2. Lawn mower according to claim 1, characterized in that the rotor is overhung in one bearing plate connectable to the housing is mounted, the bearing point being the cutting blades is facing. 3. Lawn mower according to claim 2, characterized in that the rotor bearing shield is the stator holding and centering on one end face. 4. Lawn mower according to claim 2 or 3, characterized by one in the hood and in Shell-side extension provided for the end shield to accommodate electrical accessories, like circuit breakers and capacitors. 5. Lawn mower according to one of claims 2 to 4, characterized in that the approximately used capacitors are attached to the rotor end shield. 6. Lawn mower according to one of claims 1 to 5, characterized in that the housing curved from the hood to the outside. 7. Lawn mower according to one of claims 1 to 6, characterized in that the housing is open on the inlet and outlet side and receives pendulum grille at the openings. 8. Lawn mower according to one of claims 1 to 7, characterized by one on the input and Spout attached shaft, which is used for transverse stiffening and at the same time the flat punched out Sheet metal strips carry the existing pendulum grille. 9. Lawn mower according to one of claims 1 to 8, characterized by preferably slot shaped air inlet openings in the hood on the side facing away from the cutting blades. 10. Lawn mower according to one of claims 1 to 9, characterized by when generating the Housing co-molded, superimposed recesses in the housing for receiving the Wheel bearing journals for the wheels at different heights. 11. Lawn mower according to claim 10, characterized in that the recesses as Slots are formed which are widened at the respective bearing journal fastening point, whereby profiles provided in the extensions on the bearing journals can be used appropriately are. 12. Lawn mower according to claim 10, characterized in that the bearing journals in one Go over the square and the slots at the bearing pin fastening points are widened so that that the bearing journals can be used so that they cannot rotate 13. Lawn mower according to one of claims 10 to 12, characterized in that the bearing pin can be fixed by means of toggle nuts. 14. Lawn mower according to one of claims 1 »to 13, characterized in that in the Two diametrically opposed recesses are provided over which the hood Handlebar can be connected to the lawn mower. 15. Lawn mower according to one of claims 1 to 14, characterized by one on the inside the housing attached, preferably vapor-deposited metallization. Considered publications:
Dipl.-Ing. Wilhelm Lehmann, "Electrical engineering and electrical drives", 5th edition, Springer-Verlag, Berlin / Göttingen / Heidelberg, 1953, p. 232; Magazine "Farm Implement & Machinery Review", Vol. 82, H. 978 of October 1, 1956, p. 914. 1 sheet of drawings 509 517/50 2.65 © Bundesdruckerei Berlin